The present invention relates to the general art of surgery, and to the particular field of minimally invasive surgery.
As discussed in the incorporated documents, there is current interest in surgical techniques that are less invasive than previous techniques. This current interest has engendered interest in many areas that were previously abandoned including coronary fastening and valve placement among other areas that will occur to those skilled in the surgical art.
Furthermore, many of these procedures include use of cardiopulmonary bypass for their execution. Cardiopulmonary bypass removes the venous blood from the heart and returns it to the circulation system of the patient through the patient""s aorta or through one of its branches after it has been oxygenated. This bypass procedure makes it possible to remove the heart from the circulation system in order to perform corrections on the heart and also makes it possible to arrest the heart so that there is a non-moving field that is relatively free of obstructions for the surgeon to work.
Numerous surgical procedures such as the just-mentioned cardiopulmonary bypass procedures require cannulation of a hollow anatomical structure such as the heart, the great vessels associated with the heart as well as other internal organs during the course of surgical procedures. Venous cannulation (where unoxygenated blood is removed from the patient""s circulation system) can be performed in the right atrium, SVC, IVC or other major venous branch. Typically, blood is removed from the right atrium by cannulas which have extensions into the SVC or IVC. A single cannula is sufficient for routine bypass procedures. Such a cannula typically has a basket-shaped area which sits in the right atrium and has an extension into the IVC. For valve procedures or in situations where it is necessary to totally exclude blood from the heart, it is necessary to drain blood from both the SVC and the IVC independently so that two cannulation sites and two cannulas are required.
Oxygenated blood is usually returned via the aorta (arterial cannulation site). This is usually accomplished with a single cannula of smaller diameter than the venous cannula since blood is pumped into the patient. The pumped blood distributes itself in the arterial system.
Cannulation sites are also necessary for other purposes. Cardioprotective solutions (cardioplegia) are often infused into the coronary arteries through the aortic root. Such solutions can also be delivered into the coronary sinus and used to perfuse the myocardium in a reverse direction (i.e., vein to myocardium to artery), which is also known as xe2x80x9cretrograde cardioplegia.xe2x80x9d Cannulation is also necessary when pressure or flow monitoring catheters are introduced into the heart or great vessels.
In short, cannulation is an essential component of many surgery procedures associated with a hollow anatomical structure such as the heart or blood vessels. Therefore, there is a need for efficient and effective means and methods for carrying out cannulation during a surgical procedure associated with a hollow anatomical structure and whenever cardiopulmonary bypass is necessary or whenever catheters or tubes must be inserted into the heart. This is especially so during minimally invasive surgery.
Many operations still require a considerable incision or port to conduct the operation, and many of these operations require hand suturing to perform the procedures. Smaller access sites must be used to effect truly minimally invasive procedures on patients. This necessitates technologies which obviate the need for suturing and other fine motor tasks which require direct visualization and hand suturing since the suturing will be difficult with the limited access associated with minimally invasive surgery.
Still further, general access restrictions make manipulations difficult and blood in the surgical field is also a cause for concern. Therefore, there is a need for providing a generally bloodless field when carrying out the steps associated with cannulation and subsequent closure of the cannulation incision. Furthermore, blood leakage may cause a problem. Therefore, there is a need for a cannulation means and method which can be carried out in minimally invasive surgery and which will minimize, if not totally eliminate, blood in the surgical field.
Since cannulation is an area which has heretofore required considerable hand suturing, there is a need for a cannulation device and method which requires only a minimal incision in the patient and eliminates the need for hand suturing. The device and any tools associated therewith could, for example, allow the cannulation of the heart by a tiny incision or port because no hand suturing would be necessary. During such a procedure, the patient could be placed on bypass by cannulas in the heart without the need for large incisions. Other examples of such nonhand sutured cannulation include procedures on any hollow anatomical structure, including blood vessels and other organs as will be known to those skilled in the medical art.
In addition to hand suturing techniques required by the prior art, the prior art discloses devices which incorporate a variety of balloon configurations which act to seal an incision site while cannulas are in place and which can also restrict the flow of blood to and through the structure, such as a major vessel. One problem with such devices is caused when the cannula is removed and the only way to re-establish patency of the vessels is to hand suture them closed. This method is not well suited to the small incisions used in minimally invasive surgery since hand suturing requires more room to manipulate tools and also to enable the surgeon to visualize what he or she is doing. Therefore, in addition to the needs discussed above, there is also a need for a device which can be placed in a patient without requiring hand suturing and which is suitable for use in minimally invasive surgery to meet these requirements as well.
In addition, older patients may have frail tissue which result in trouble pulling purse-string sutures tight. In some cases, the sutures will cut the tissue causing further leaks which must be patched and sutured again. Therefore, there is a need for a means and a method for setting a cannula in a patient who may have fragile and/or friable tissue, especially in minimally invasive surgery.
It is also noted that anchoring a cannula in tissue stresses that tissue by transmitting any forces associated with the cannula or movements of the cannula to the tissue. As is especially the case with frail tissue, such anchoring may tend to tear the tissue. Therefore, there is a need for a means and a method for attaching a cannula to an anatomical structure in a manner that reduces or eliminates cannula-induced stress on the tissue.
Closure of purse-string sutures causes the tissue to be gathered and bunched resulting in a loss of cross-sectional area and/or a decreased function. Therefore, there is a need for a means and a method for gaining access to the interior of an organ or a vessel that can be closed without causing bunching and/or gathering of the patient""s tissue.
Still further, in manually sutured procedures a substantial amount of tissue is required to make a port closure. For example, when the atrium of the heart or the aorta is cannulated with a purse-string suture the tissue inside the purse string is lost when the suture is tied. This causes stretching and deformity of the heart or aorta when the purse-string is tied, sometimes leading to tears in the tissue and/or leaks. Therefore, there is a need for a means and a method for cannulating organs which does not require purse-string sutures.
Specifically, surgeries on many organs also require opening the organ and/or the vessels associated with therewith. The vessels must be closed at the end of the procedure to complete the operation. It is important to minimally invasive procedures to have a tool which will allow closure of such organs and vessels without the need of hand suturing.
For example, the replacement of the aortic valve requires cannulation of the aorta and the right atrium for the commencement of cardiopulmonary bypass. The aorta is then opened above the aortic valve and the defective valve is removed and then replaced. The aorta must then be closed hemostatically and the cardiopulmonary bypass pump discontinued followed by removal of the cannulas from the heart. In order for this procedure to be performed through truly tiny apertures in the patient, there is a need for a means and method for mechanically opening and closing the aorta.
As can be understood from the above discussion, a device which opens an organ or other such structure and allows it to be closed by a simple tightening of a suture without the need for placement of hand-placed stitches is needed. The device should take into account that many patients have weak and friable tissue. Often when a structure such as a great vessel is closed with sutures the tissue wall tears at the sutures. The prior art deals with this problem by applying surgical felt to the leaky areas. However, the felt is secured with sutures and more holes and tearing can occur at the patch site. Therefore, it is desirable to have a closure device and method which will reinforce frail tissue and reduce tears.
High doses of anticoagulants are usually administered to patients undergoing heart surgery, such as cardiopulmonary bypass, to prevent blood clots during the surgery. These drugs prevent the clotting process from starting in the centrifugal extracorporeal pump circuit. However, these same drugs make it difficult to get large incisions in the vessel walls and heart muscle or other internal organs to seal. Therefore, there is a need to provide a hemostatic medium which is held in the proximity of a wound to prevent blood loss until the patient""s natural clotting cycle can seal the wound. In addition, a mechanical means to hold the organ or vessel walls in tight approximation is needed to ensure stability and security of wound closure.
As discussed above some procedures require multiple access sites. In such situations sealing the tissue to the cannulation incision is very difficult. Often, two separate sites are required. In some instances multiple access sites will multiply the above-discussed problems. Therefore, there is a need for a means and a method for providing multiple access sites to internal organs which can be effectively and efficiently sealed.
It is a main object of the present invention to provide a leak-free method of cannulating of an internal organ.
It is another object of the present invention to provide a leak-free method of cannulating a vessel.
It is another object of the present invention to provide a unique docking mechanism for a bypass cannula.
It is another object of the present invention to provide an apparatus and method for cannulation which can reinforce the tissue to which the cannula is attached.
It is another object of the present invention to provide an apparatus and method for quickly closing a cannula incision in great vessels, organs or ventricles.
It is another object of the present invention to provide an apparatus and method to cannulate vessels in minimally invasive surgery with small access restrictions.
It is another object of the present invention to obviate the need to suture within a narrow minimally invasive access site.
It is another object of the present invention to provide a cannulation port which closes the port wound with a minimum amount of bunching or gathering of tissue.
It is another object of the present invention to prevent loss of atrium or vessel size on closure of a cannulation site.
It is another object of the present invention to minimize leaks on closure of a cannulation port.
It is another object of the present invention to provide an apparatus and method for sealing an incision instrument against a valve used in cannulating the patient as the cannulation port is being defined.
It is another object of the present invention to provide a single access port which can accommodate more than one cannula without leakage.
It is another object of the present invention to provide an apparatus and method for purging air from the cannulation port.
It is another object of the present invention to allow closure of a cannulation site after it is needed by simply drawing up one suture.
It is another object of the present invention to provide an apparatus and method for gaining access to vessels in minimally invasive surgery within small access restrictions.
It is another object of the present invention to provide an apparatus and method for gaining leak-free access to and closure of great vessels of the heart and other anatomical structures without placing sutures in the anatomical structure.
It is another object of the present invention to prevent loss of atrium or vessel size or volume on closure of a cannulation access device.
It is another object of the present invention to provide an access and closure port for an internal vessel or structure that provides a minimum amount of bunching or gathering of tissue on closure.
It is another object of the present invention to provide a cannulation access device with a malleable frame which holds the incision open when desired.
It is another object of the present invention to provide a cannulation access apparatus and method which can reinforce the tissue to which it is attached with a mechanical fastener.
It is another object of the present invention to provide an access and cannulation and closure device that approximates the edges of the tissue to which it is attached to improve healing.
It is another object of the present invention to provide an access and closure device which includes a hemostatic medium to promote healing of the incision.
It is another object of the present invention to provide a built-in closure means to allow simple closure of the access site with a minimum of effort.
It is another object of the present invention to provide an apparatus for providing access to the interior of an anatomical structure that will act as a stress relief element and will isolate an instrument, such as a cannula, from the tissue whereby instrument-induced forces will not be transferred to the tissue.
These, and other, objects are achieved by a device for establishing restricted access to a hollow anatomical structure such as a vessel, a heart or any internal organ of a patient during surgery. One embodiment includes a flexible sleeve and a malleable frame that is mounted on the wall of the structure adjacent to an incision in the wall of the structure and a one-way port on the sleeve through which a cannula is inserted to access the interior of the anatomical structure, and a suture on the sleeve for closing the sleeve and approximating the tissue adjacent to the incision into a healing position after completion of the procedure.
Incorporated applications Ser. Nos. 08/714,615 and 09/200,796 describe a mechanical fastening device used for coronary vessel anastomosis. Another embodiment employs such a fastening device and includes a malleable anchor ring with a multiplicity of tines that attach to the vessel or organ. The ring has a material memory such that once deformed it remains in the deformed configuration until physically moved to another configuration. This ring is easily mounted on a vessel or other organ adjacent to an incision and is easily deformed to open or close the incision as desired. The present invention utilizes this malleable ring as an anchor element for a cannulation port.
The cannulation device of the present invention can be placed and configured on the vessel or organ during minimally invasive surgery, and can be closed after use from outside the patient. By selecting from a plurality of different sleeves, the type of access and cannulation can be easily selected. For example, single or multiple cannulas can be accommodated by the device of the present invention.
Because the device is easily set and closed small sites can be accommodated, and virtually no blood will seep into the surgical field. Furthermore, since no hand suturing is required to close the site all of the above-discussed problems associated with suturing and hand suturing in particular, are eliminated. The mounting tines of the mounting ring anchor the ring in a manner that will not endanger tissue, especially fragile tissue, and thereby will reduce or eliminate the problems associated with damaging tissue due to placing and sealing an access port. The sleeve is flexible and isolates the cannula from the malleable ring and thus relieves stress that otherwise might be transferred from the cannula to the tissue.
Because of the secure nature of the mounting, leaks are virtually non-existent, even in fragile tissue.